Article and material containing organic derivatives of cellulose



jmfzl, 193. J H ,BROWN 2,32%1 ARTICLE AND MATERIAL CONTAININGVORGANI'C DERIVATIVES OF CELLULOSE Filed Nov. '7, 1955 ATTORNEYS Patented June 21, 1938 UNITED STATE ARTICLE AND MATERIAL CONTAINING oacA Ic DERIVATIVES or CELLULOSE l Joseph H. Brown, Brooklyn, N. Y., assignor to Celluloid Corporation, a corporation of New Jersey 1 Application November 7, 1935, Serial No. 48,663

4 Claims.

This invention relates to a permanently pleated and'shaped sheet, film or foil containing a derivative of cellulose and to the articles made therefrom. I Y i This application is a continuation-in-part of my co-pending application S. No. 19,384, filed May 2, 1935, which has issued as Patent No. 2,025,568, and my copending application S. No. 41,629, filed September 21, 1935.

An'object of this invention is the economic and expeditious production of pleated and embossed sheets, films or foils containing derivatives of cellulose. A further object of this invention is the preparation of materials suitable for decorative purposes, which materials are substantially moistureproof and resistant to weather changes. Other objects of the invention will appearfrom the following detailed description.

As is known, pleated. sheeting materials of paper, fabric, etc. have been used inthe lamp shade industry. Such pleated materials'have not been entirely satisfactory, due to the fact that the pleats thereof had to be stitched in to hold them in shape and after stitching it was impossible to place the same over irregular lamp shade forms or other articles. Where paper, parchment and like materials in pleated form were used, the pleats when'once pulled out, either intentionally or accidentally, rendered the material unfit for its intended purpose as it no loh'gerhugged and fit the form but remained permanently distorted. By employing this invention, which in general terms may be described .as pleating then embossing thin sheets or foils of a derivative of cellulose, there is produced an article which may be stretched over form's'ofirregular shape and which always tend to resume the shape it had before being stretched over the form.

In accordance with this invention, there may be formed lamp shades orother articles that have a crystal clarity which feature cannot be produced in paper, parchment, fabric, etc. Moreover the material may beformed of any desirable thickness of sheet material so that it may possess a degree of strength suitable for the purpose intended and still retain its crystal clarity.

A further advantage of the'article produced in accordance with this invention is that it practically moisture-proof and resistant to weather changes. Thus, the material may be used in moist or damp places or extremely dry places without any substantial change in its form being effected, such as, for example, the release of the pleats or the drooping of the material when the article is kept in damp places, or the cracking and splitting of the material when the article'is kept in extremely dry places. Another desirable property of the material produced in accordance with this invention is that an article made therefrom may be sponged, washed and otherwise cleaned without damage thereto since the pleats arenot removed, and the material is not streaked by the dirt, in the cleaning of the article.

The material made in accordance with this invention. also has the advantage over paper, fabrics and parchment, etc. in that it has no nap or filament ends to catch dust and other materials such as normally collect on lamp shades of paper, parchment and textile fabric. The surface of the new material is substantially smooth and does not act as a trap for dust particles and lint.

A further advantage of this invention is that although the sheeting material may be very thin and light in ,weight'it is very durable even when pleated, and unlike paper, parchment or other sheeting material, is not readily torn. Not only is the material. durable but it also retains its pleated shape .under all atmospheric conditions without necessitating the sewing thereof, thus offering a marked advantage over silk and other .fabrics whose edges must be sewed together to maintain the pleat.

The pleated and embossed sheets or foils made in accordance with this invention exhibit ,a unique rubber elasticity. They can stretched an appreciable distance before permanent deformation takes place. In making a lamp shade, for example, a rectangular blank of pleated and embossed sheeting material containing a derivative of cellulose is cut and the two ends are cemented together with any suitable cellulose ester film cement. which is in tubular form is stretched over the frame of a lamp shade, it will be found that the When this sheet formed sheet hugs the frame-tightly and con-.

forms to the. shape of the frame even in the case .where the form of the .frame is concave.

This is a distinct advantage, since it not only makes for economy of material but also insures permanency of form. Lamp shade blanks, as heretofore made, were'usually stamped out in irregular or circular form. However, in the case I of pleated sheets containing derivatives of cellulose, the blanks may be rectangular in form regardless of the shape of the frame they are to fit, thereby resulting in very little, if any, wastage of material; The elasticityof the pleated prod-' not can be appreciated when it is known that there is usually a length shrinkage of about 80% when placing the pleats in the material, which pleated product .may be pulled out or stretched to substantially its original length and upon being released returns to its shrunken length. In other words, a strip of foil 100 inches long when pleated in pleats of about of an inch measures" "only 20 inches in length: The re-' sultant elasticity, resiliency or tendency to return to its short length when the pleated foil is m stretched is profitably utilized in covering and wrapping many articles of irregular shape. All other products such as paper, parchment, sheets of gelatin, sheets of regenerated cellulose, fabric, etc. do not exhibit this remarkable stretching characteristic which makes the material of the present invention particularly desirable for use -in wrapping, covering or decorating articles of irregular shape.

While the material of .this invention may be of crystal clear transparency, it may also be, attractively decorated With-designs by printing, lacquering, stenciling, etc. applied prior to, during or subsequent to the embossing thereof. Furthermore, the base material may contain various efiect materials which alter its transparency, thus producing a material which may be translucent, opaque or mottled. These transparent, translucent and opaque efl'ects may be uniform throughout the whole area of the material or may be contained in the base material only in local areas. 'Moreover, these various effects may be produced in the material without adding materially to the weight thereof and without afterwards altering the physical characteristics of the clear product. The articles made therefrom are extremely light in weight, are odorless and are permanent as to their shape, color, transparency, etc.

-A distinct advantage of the material in the present invention is that when using the crystal clear product it allows for the transmission of ultra violet light rays. This quality is of great advantage when employing the material as lamp shades, screens, etc.

In accordance with my invention, I prepare a sheet, film or foil containing a derivative of cellulose with or without a plasticizer by inserting I bends or pleats in the sheet, film or foil under heat and pressure so that they are-retained by the sheet, film or foil substantially permanently. These pleated sheets, films or foils are then smoothed out or flattened in a part of the pleated area, leaving the pleats of other areas of the material raised above the plane of the flattened portions and at an angle thereto. and embossing of the sheet material in this manner results in a product which may be pulled out to straighten it, and while under this stress the material exerts a strong force to resume its pleated shape, giving the effect of an elastic material. The product of this invention, therefore, is a sheet material containing pleats with the pleats of certain areas of the sheet lying in substantially the plane of the sheet while the pleats of other areas are raised and are at an angle to the plane of the sheet.

Any suitable thermoplastic sheet, film or foil made of or containing derivatives of cellulose may be pleated and embossed or employed as the base material in forming the pleated and embossed sheets. Sheets, films and foils of organic 'inch to .015 inch, preferably from .0008- inch to .003 inch. Although cellulose acetate is the organic derivative of cellulose which is preferably employed as the base of sheet material, other suitable organic derivatives ofcellulose maybe employed, such as the organic acid esters of cellulose and the cellulose ethers. Examples of the The pleating organic acid esters of cellulose are cellulose formate, cellulose butyrate and cellulose propionate ethyl cellulose and benzyl cellulose. While organic derivatives of cellulose as the base materials are preferred, cellulose nitrate foils and films may also be satisfactorily pleated with heat and pressure. After the sheet of cellulose nitrate has been formed into pleats, the pleated sheet may be given a denitrating treatment with alkaline solutions such as caustic soda, sodium hydrosulphide, etc.

The sheet stock to be pleated and then embossed preferably contains from 5-l00% or more, based on the weight of the cellulose derivative present, of any suitable plasticizer. The amount of plasticizer employed depends upon the type and amount of effect materials, if any, contained in the sheets. 'Although any suitable plasticizer may be employed for forming the crystal clear thin organic derivative of cellulose sheets having especially high resiliency, it is preferable to employ from 5-30%, based on the weight of the organic derivative of cellulose present, of dibutyl phthalate However, any plasticizer which is suitable for the particular cellulose derivative or mixture of cellulose derivatives employed may be used. The

' plasticizers may be any of the high boiling s01- ters of phosphoric acid, e. g. tricresyl phosphate;

themixed alkyl and aryl phosphates, e. g. ethylglycol dicresyl phosphate; and camphor.

The sheet stock which is to be pleated may contain any suitable efiect materials to alter the transparency, resiliency, color, handle, fluorescence or other properties of the material. Thus, such effect materials as pigments, filling materials, dyes or lakes, fire retardants, plasticizers, waterproofing agents, etc. may be'employed. Examples of fire retardants are beta chlornaphthalene, triphenyl phosphate, tricresyl phosphate, etc. Examples of filling materials that may be employed are powdered metals such as aluminum powder, bronze powder, etc., oxides and salts oi metals such as antimony oxide, tin oxide, silky variety of mercurous chloride, lead iodide, lead oxide, lead carbonate, etc., or other filling materials such as powdered glass, metallic threads or lahm, organic materials such as fibres of cotton, wool, etc. or organic compounds such as res-' ins; etc. Those resins may be employed that have a tendency to improve the retention of the plasticizer by the cellulose derivative as more 'fully disclosed in U. S. Patent No. 1,930,069. These 'efiect materials may be incorporated in the sheet,

film or foil stock by mixing the same with the solution from which they are formed, or by rolling them into the material during the formation of the film, foil or sheet, of by applying the'same to the formed sheet in the presence of suitable solvents or swelling agents. v

The sheet, film or foil may be pleated in any suitable manner, for instance, by running the same through a fabric pleating machine after having placed on either or both sides 01 the sheet while examples of ethers are methyl cellulose,

ner, producing effects in raised andflat pleats,

"a thin sheet of paper as a guide and/or protection. The stock may be conditioned prior to passing it through the pleating machine by passing the same through a steam chamber, a chambercontaining solvent vapors for the material of the stock, through a heated chamber, or through a heated liquid such as water. The material may be shaped into any desired form of pleat. I prefer, however, that the space between the bends of the material upon itself be of the order of less than one-half inch and more pref erably of the order of inch or less. Sheets having pleats of about one-eighth inch between bends have been found to be highly suitable for lamp shades and similar uses. However, larger or smaller pleats may be employed. The material may be formed intoaccordion pleats, box pleats, crystal pleats or other types of pleats, or

, the material may have more than one type of pleat formed therein.

,When inserting pleats in the sheet, film or foil, it is preferable to set the pleat in the material by the aid of. heat. The pleating roll of the pleat-,

ing machine may be heated by any suitable means, as by steam, electric conductance or resistance coils or open flame, in such a manner that the material while being held in the pleated form, by steel bands or other pressing device, is plasticized or softened suiiiciently that any stress in the material to straighten out is removed. For the purpose of setting the bends in the material prior to any considerable amount of handling of the material, the material, while in the pleated form, is cooled by the air or it may be cooled by passing the same over a metallic roll or other device having a cooling medium circulating therein. By

this means the micelles in the base materialare rearranged in such a manner that the bends forming the pleats are-made permanentor substantially so, giving to the material the property of exerting a force such that when pulled out it tends to return to its tightly pleated condition.

The sheet base material after having been pleatedmay be subjected to an embossingaction, by means of heat and pressure, whereby local areas on the surface of the sheet have the pleats flattened to a very tightly closed position while other areas which are not subjected to heat and pressure have the pleats in a partially opened condition. By embossing the pleated material by means of heat and pressure and then cooling the material prior to extensive handlingthe embossed figure may, be permanently set in the material.

The embossing of the sheet material may be acswedging action, i. e. where one plate or roll of complished by means of flat presses having a male and female plate or a fiat plate and an engraved plate, one or both of which are heated or byem-- bossing rollers one or both of which are engraved and one or both of which are heated. Furthermore, the sheet material may be embossed by a theembossing device is of a resilient material that pushes the sheet material into the opening of the other plate or roll.

By this invention very desirable flat, flexible, high decorative materials may be formed. For instance, the pleated foil which may have a colored lacquer applied on one or both sides maybe attached to any suitable base, such as flannel,

sheet material, .etc.,, by

felt, paper, natural or artificial silk, artificial any suitable cement.

' Contact between 'thepleated material and these basesis made only at the edges of the pleats. The assembly with raised pleats is then placed into a press and embossed in any desirable manand at the same time a lamination between the V flat pleats and the backingof sheet material is effected. The same lacquering and embossing.

operation may be performed on pleated material wherein the pleated film, foil, etc. isnot attached to a backing-of flexible sheet base material. The

- of the pleated material to hold or weld it to metal frames, such as lamp shade frames and the like. Thus, in the case of a concave lamp shade, when the pleated and embossed cylindrical stockingis stretched over the frame, there will be a tendency of this material to spring upwards unless it is attached to the frame either by welding 1 it thereto with cement or binding it thereto with a suitable'tape or braiding. Suitable tape or braiding. may be formed or molded from an organic derivative of cellulose or woven from textile materials, and the same may be attached to the pleated sheet material by applying a solvent or cement to the pleated material and pressing the tape or braiding into the softened material.

The pleated and embossed sheet material niay be laminated onto other sheet material such as fabrics, paper, felt, leather, wood, glass, etc. For

the purpose of causing an adhesion, between the preformed pleated and embossed sheet material and other sheet material, any suitablecementing agent may be employed.

Two or more layers of the pleated and-embossed material having the same size pleats or.

diiferent size pleats maybe imposed one upon the other with or without additional material between the layers. The pleats in the two layers may be caused to run parallel and the embossing matched or the pleats may be run at right angles toeach other to produce novel eilects, particularly when the different layers have variegated color eiiects. The layers may besuperimposed upon each other before, during or after the embossing step. The pleated and embossed mate-- rial may also be stretched fan shaped and the fan may be cemented to glass or other base material to yield ornamental radiating effects suitable for placing at the back of wall lights, lights on mirrors and the like. Thisuse of the material produces a most striking effect when lacquered an elastic-like material may be formed that has a-cloth-like appearance by cementing a fabric .to one or both sides of a film containing an organic derivative of cellulose and pleating the same in the presence of heat and under pressure Also the'film or toll containing an organic derivative of cellulose may be laminated with a film U. s. Patents Nos. 1,981,141and 1,835,619. Thus,

or foil having an embossed surface in imitation of crepe or other ornamental effects.

A further modification may be formed by laminating an edging, such as a fold of paper, metal foil, cotton fabric, rayon fabric, cellulose acetate fabric or transparent sheet material of regenerated or reconstituted cellulose, to the sheet material containing an organic derivative of cellulose which itself may be laminated as described above. After laminating the sheet material with the other materials the same may be pleated and embossed. By this means both ornamental and protective edgings may be placed on the material. An example of this modification is in pleated and embossed collars for women or children, which are edged with a fabric to reduce the tendency of thesharp corners of the pleated material to irritate the skin by contact therewith. f

The material, regardless of 'the shape. in which it is formed, may be sprayed, brushed, dipped or otherwise treated with lacquers, varnishes, etc. in the form of solid colors, variegated colors in patterns, or flowers. Other designs may be stencilled or painted on the material. This produces, when using the crystal clear material,

novel eifects not attainable by the use of any other material now known in the art.

In the claims the term sheets is intended to include sheets, films. and 'foils that may be formed by any suitable method. For instance, sheets may be formed by cutting the same from a solid block of an organic derivative of cellulose and plasticizer that may have been block-pressed in the presence of heat, while films and foils may be formed by extruding a solution of an organic derivative of cellulose, in a volatile solvent, through suitable orifices into an evaporative or precipitating medium, or they may be formed by casting the solution upon a surface, preferably a film casting wheel or the like.

For the purpose of aiding in the description of this invention, the same will be described with particular reference to the drawing. drawing, wherein like reference numerals refer to the same or similar elements in the respective figures,

Fig. 1 is a plan view of a sheet of material pleated and embossed in accordance with'this invention,

Fig. 2 is a sectional view taken on the line 2-2 of Fig. 1,

Fig.3 is a plan view of a'sheet material. containing a backing produced in accordance with this invention,

Fig. 4 is a sectional view taken on the line 4-4 of Fig. 3,

Fig. 5 is a plan view of a sheet material made in accordance with this invention,

Fig. 6 is a plan view of the same sheet containedin Fig. 5, the pleats of same being opened The article I formed of the film, foil or sheet of the organic derivative of cellulose may comprise a plurality of pleats 2which, prior to embossing, remain in a fairly open state as at 3. By heat pressing this pleated sheet material in local areas, the pleats of those areas pressed become flattened as at 4. In this manner novel designs may be made and articles produced havappearance shown in Fig. 5.

In the ing effects that could not be produced in any other way. The material has an elastic-like property, the degree of stretch being inversely proportional to the thickness of the sheet material employed as the base material.

A modified form of the invention is shown in Fig. 3. In this modification the article is formed of a pleated foil 5 cemented to a backing material 6. Prior to embossing the assembly the backing material is cemented to the pleated material only at the edge of the pleats as at I. This material may be embossed by an embossing device having any suitable design thereon. The resultant product is a sheet material having fiattened pleated areas 4 and raised or open pleated areas 3 while the flattened areas of the sheet material is permanently attached to the backing material.

In Figs. 5, .6 and 7 there is shown a sheet material similar to that shown in Fig. 1 but having a different design embossed thereon. This sheet consists of pressed areas 4 wherein the pleats are flattened almost into a single plane and .areas 3,,where the pleats stand somewhat at an angle to the plane of. the material. This material when not under any stress would have the However, after this material is pulled out or stretched the pleats open up giving the appearance shown in Fig. 6. Upon releasing the material from the stretching stress the material will snap back into the position shown in Fig. 5 in a rubber-like manner. As shown in Fig. 6, the embossed design of the material is not removed when the material is stretched.

It is to be understood that the foregoing detailed description and drawing are merely given byway of illustration, and many variations may be made therein without departing from the spirit of my invention.

Having described my invention, what I desire 'to secure by Letters Patent is:

' of its pleated form.

2. An article of manufacture comprising a rigid form having the exterior of the same covered with a sheet of cellulose acetate containing pleats, certain areas of the pleats lying in the plane of the article and the other areas of the pleats standing at an angle thereto, said sheet be extensible without loss of its pleated form.

3. An article of manufacture comprising a film or foil containing an organic derivative of cellulose and having pleats formed therein, certain areas of the pleats lying in substantially the plane of the article and the other areas having the pleats standing at an angle thereto, said sheet being extensible without loss of its pleated form.- v

4. An article of manufacture comprising a film or foil containing cellulose acetate and having 

